Combined Computational and Experimental Studies of the Mechanism and Scope of the Retro-Nazarov Reaction
作者:Michael Harmata、Peter R. Schreiner、Dong Reyoul Lee、Patrick L. Kirchhoefer
DOI:10.1021/ja048942h
日期:2004.9.1
have a rate-accelerating effect on the retro-Nazarov reactions of these species. The retro-Nazarov reaction of these intermediates is predicted to exhibit significant torquoselectivity when carbon three is substituted with a methoxy and a methyl group. Experimental studies show that oxyallylic cations can undergo effective retro-Nazarov reactions when two alkyl and one aryl/vinyl groups are on carbons
密度泛函理论计算 (B3LYP/6-31+G) 表明,环戊烯氧基烯丙基阳离子的碳三和四处的共轭和给电子取代基应该对这些物种的逆 Nazarov 反应具有加速作用。当碳三被甲氧基和甲基取代时,这些中间体的逆-纳扎罗夫反应预计将表现出显着的扭矩选择性。实验研究表明,当三个和四个碳原子上有两个烷基和一个芳基/乙烯基时,氧烯丙基阳离子可以进行有效的逆 Nazarov 反应。相同数量的烷基取代基或单个芳基取代基对促进反应无效。有趣的是,碳三上的单个烷氧基取代基足以发生逆向纳扎罗夫反应。